Wiper drive unit and method for mounting said wiper drive unit on a support frame

ABSTRACT

The invention relates to a wiper drive comprising a housing, a reversing motor and a gear mechanism connected downstream of the reversing motor, wherein a swaying element for driving at least one wiper arm or a wiper arm rod is provided on the gear mechanism output shaft, and wherein the operating range of the swaying element lies within a pivoting range which is delimited by two mechanical stops, wherein at least one stop is designed such that it can be removed and/or moved in such a way that the swaying element, when the wiper drive is mounted on a support frame, can be moved from a first mounting position, which lies outside the pivoting range, into the pivoting range without being obstructed by the stop. The invention furthermore relates to methods for mounting a wiper drive on a support frame.

The invention relates to a wiper drive comprising a housing, a reversingmotor and a gear mechanism connected downstream of the reversing motor,wherein a swaying element for driving at least one wiper arm or a wiperarm rod is provided on the gear mechanism output shaft, and wherein theoperating range of the swaying element lies within a pivoting rangewhich is delimited by two mechanical stops.

Reversing motors for use in wiper drives, in particular for windscreenwiper systems of motor vehicles, are characterized in that theirdirection of rotation can be reversed in a manner corresponding to thewiper blades moving back and forth on a windscreen or rear window. Thishas the advantage that a rod assembly for driving two wiper arms can beof very small design or that each wiper arm can be operatedindependently by coupling to a dedicated drive motor and thus there maybe no need for a transmission rod assembly.

The reversal of the direction of rotation is achieved by electricalcontrol of the reversing motor. The reversing motor thus drives thedownstream gear mechanism and also the swaying element provided on thegear mechanism output shaft, which swaying element in turn is suitablefor driving a wiper arm or a wiper arm rod until the wiper arm hasreached one of its end positions on a windscreen to be cleaned. In theend position of the wiper arm, the reversing motor is actuated such thatits direction of rotation is reversed, so that the wiper arm is drivenin the opposite direction until the wiper arm has reached the other endposition. The wiper arm is thus moved within its operating range betweenthe end positions of the wiper arm by a suitable control mechanism.

If there is a fault in the control mechanism of the reversing motor,there is the risk that the wiper arm or the wiper arm rod will be movedbeyond the limits of the operating range. The wiper arms coupled to theswaying element thus move beyond their wiping range and may cause damageto the vehicle body or to units within the engine compartment. Moreover,the wiper drive itself may also be damaged.

In order to prevent such damage in the event of a fault in the reversingmotor control mechanism, it is proposed according to WO 02/22409 A1 thata drive element connected to a motor crank cooperates with stops whichprevent any swaying beyond the turning positions of the windscreenwiper. This is a simple and effective measure for preventing damage tothe vehicle, to vehicle units or to the wiper drive in the event offaults in the reversing motor control mechanism.

However, it is disadvantageous in the aforementioned prior art that thechecking and mounting of the wiper drive is complicated, and reliableoperation is not ensured after a long operating time. In order to beable to check that the motor/gear mechanism unit, which is not yetmounted on a support element, is running true, a swaying element isplaced on the gear mechanism output shaft. Once the check of the runningis complete, the swaying element is removed again from the gearmechanism output shaft and the motor/gear mechanism unit is mounted on asupport element which bears the abovementioned stops for delimiting thepivoting range of the wiper drive. Finally, the swaying element isplaced on the gear mechanism output shaft in such a way that the freeend of the swaying element can be pivoted between the stops.

Based on this, it is an object of the invention to further develop awiper drive of the generic type such that the mounting operation issimplified.

According to the invention, this object is achieved in a wiper drive ofthe type mentioned above in that at least one stop is designed such thatit can be removed and/or moved in such a way that the swaying element,when the wiper drive is mounted on a support frame, can be moved from afirst mounting position, which lies outside the pivoting range, into thepivoting range without being obstructed by the stop.

Since at least one stop is designed such that it can be removed and/ormoved, the swaying element can be moved out of a first mounting positionand into the pivoting range when the wiper drive is mounted on a supportframe, which support frame is usually fixed to the body. The firstmounting position lies outside the pivoting range. The pivoting range isdelimited by two mechanical stops, of which at least one stop isnevertheless designed such that it can be removed and/or moved.

During normal operation of the wiper drive, the swaying element movesonly within an operating range which lies within the pivoting rangedelimited by the two mechanical stops. This has the advantage that theswaying element and the stops do not touch one another during normaloperation, which would result in the components being subjected tomechanical stress and in undesirable noise being produced. The swayingelement strikes the mechanical stops only if the reversing motor controlmechanism has a fault, so that the movement of the swaying element isthen limited to the pivoting range delimited between the mechanicalstops.

According to a first embodiment, at least one stop is arranged on atleast one add-on element such that it cannot be removed, wherein theadd-on element can be releasably fixed on a component of the wiperdrive, in particular on the housing. In this embodiment, therefore, thestop cannot be removed directly from the wiper drive and/or cannot bemoved relative thereto; rather, the stop is provided on an add-onelement which for its part can be releasably fixed on a component of thewiper drive, and in particular on the housing. This has the advantagefirstly that the handling of the stops during mounting thereof isfacilitated, and secondly that further functions can be implemented bythe add-on element.

Both stops may be provided on one add-on element or else one stop may beprovided on each of two add-on elements. When using one add-on element,the number of components is minimized; a saving in terms of material andweight can be made when using two smaller add-on elements.

As already mentioned, further functions can be implemented by an add-onelement. Advantageously, at least one add-on element is suitable forexerting a retaining function for a connection between the housing and asupport frame. The add-on element therefore serves not only as a supportfor one or two stops, but also as a fixing element for ensuring aconnection between the housing of the wiper drive and a support frame.By integrating the stop and retaining functions in one component, thenumber of components of the wiper drive can be reduced and the mountingof the wiper drive can be considerably simplified. As a result,particularly cost-effective manufacture is possible.

In one refinement of the invention, the add-on element can be releasablyfixed on a component of the wiper drive, in particular on the housing,in various orientations and/or at various positions. This has theadvantage that the add-on element or add-on elements can be used indifferent installation situations which arise for example when areversing motor assumes different relative positions with respect to thewindscreen to be cleaned in different vehicles. The pivoting range canthus be set in a variable manner by the add-on elements which can bereleasably fixed on the housing in various orientations and/or atvarious positions. The same add-on element can then be used in differentwiper drives, as a result of which different wiper drives can berepresented by the same components.

The add-on element can be fixed on a component of the wiper drive, inparticular on the housing, at at least one, preferably at several,fixing points. When using one fixing point, the add-on element can bemounted in a particularly simple and rapid manner. However, in order tobe particularly able to deflect forces and moments which may arise whenthe swaying element strikes a stop, it is advantageous to provide atleast two fixing points for the add-on element. The add-on element isthus secured on the housing of the wiper drive such that anydisplacement of the stop when it is hit by the swaying element is ruledout, so that the stops can reliably delimit the pivoting range of theswaying element.

The add-on element is preferably designed as a shaped part made of sheetmetal. In this way, even add-on elements which implement a number offunctions at the same time and therefore may have a complex geometry canbe manufactured in a very cost-effective manner.

It may be advantageous if the add-on element is non-releasably connectedto the support frame. By virtue of this measure, it is possible to savea handling step during mounting of the wiper drive, since the add-onelement and the support frame already have a defined relative positionwith respect to one another. The non-releasable connection may beproduced for example by welding, soldering, adhesive bonding orriveting.

According to a second embodiment of the invention, at least one stop isprovided as a separate component which can be fixed on a component ofthe wiper drive, in particular on the housing. As a result, the at leastone stop can be designed in a particular simple and stable manner.Existing wiper drives can be equipped or retrofitted particularly easilywith the delimitation of the pivoting range according to the invention.If two stops are provided as separate components, the reversing motorcan also be used for rotational operation. In this way, there is no needto provide two different motors for wiper drives in the reversing modeand in the rotational mode.

In one refinement of the invention, the at least one stop is provided asa pin. Such a pin has for example an essentially cylindrical shape andcan be inserted for example with a press fit into the housing of thewiper drive. The pin may also already be arranged in the housing priorto mounting of the wiper drive on a support frame, and be displaceablerelative to the housing. The pin extends essentially perpendicular tothe plane in which the swaying element moves. A stop for delimiting thepivoting range of the swaying element can thus be formed using simplemeans.

According to a third embodiment, the stops cooperate with a stop elementwhich is provided on or in the swaying element such that it can be movedand/or removed. This has the significant advantage that the stops mayalready be integrated in the housing of the wiper drive and that theswaying element can be brought into its pivoting range without anyproblems. When the swaying element is located in the pivoting range, thestop element can preferably be placed essentially perpendicular to theplane in which the swaying element moves, so that the stop element cannow cooperate with the stops and prevents any movement of the swayingelement out of its pivoting range.

The stop element may be designed for example as a pin which is slidablymounted in the swaying element and can be slided from a position inwhich it does not cooperate with the stops on the wiper drive into aposition in which a movement of the swaying element beyond the stops isnot possible.

Advantageously, the stops are made in one piece with a component of thewiper drive, in particular with the housing. By way of example, thestops are part of a cast housing so that the additional mounting ofstops on the housing is not required. As a result, a mounting step canbe saved.

Advantageously, the support frame on which the wiper drive can bemounted is designed as a tubular element. This has the advantage thatthe position of the wiper drive can be set within a number of degrees offreedom. For example, the wiper drive can be displaced along the lengthof the tubular element and can also be rotated around the latter, sothat an optimal setting of the wiper drive with respect to the supportframe or with respect to a windscreen of a vehicle is possible.

Advantageously, the swaying element is non-releasably connected to thegear mechanism output shaft. This prevents the formation of any playbetween the swaying element and the gear mechanism output shaft duringoperation of the wiper drive, and thus any play in the movement of thedriven wiper arm or wiper arm rod. A non-releasable connection may beformed for example by welding, pressing-on or caulking.

The invention furthermore relates to a method for mounting a wiperdrive, in particular a wiper drive according to the invention, on asupport frame, wherein the wiper drive comprises a housing, a reversingmotor and a gear mechanism connected downstream of the reversing motor,wherein a swaying element for driving at least one wiper arm or a wiperarm rod is provided on the gear mechanism output shaft, and wherein theoperating range of the swaying element lies within a pivoting rangewhich is delimited by two mechanical stops, wherein the followingmounting steps are carried out:

a) mutual orientation and positioning of housing and support frame,wherein the swaying element assumes a position outside its pivotingrange,

b) mounting of a first stop on a component of the wiper drive, inparticular on the housing,

c) fixing of the housing on the support frame,

d) pivoting of the swaying element into the pivoting range, and

e) mounting of a second stop on a component of the wiper drive, inparticular on the housing.

The abovementioned steps may also be carried out in a different order,in particular in the order a), d), b), e) and c) or a), c), d), b) ande). Instead of steps b) and e) of the last-mentioned order of mountingsteps, there may be displacement of a stop element which is provided onor in the swaying element such that it can be moved and/or removed.

The individual mounting methods and advantageous refinements and detailsof the invention can be found in the following description, in which theinvention is described and explained in more detail with reference tothe examples of embodiments shown in the drawing.

In the drawing:

FIGS. 1 a-e: show a wiper drive with one add-on element;

FIGS. 2 a-c: show a wiper drive with two add-on elements;

FIGS. 3 a-c: show a wiper drive with an add-on element according to asecond embodiment;

FIGS. 4 a-c: show a modification of the embodiment shown in FIGS. 3 a-c;

FIGS. 5 a-d: show a wiper drive with a stop provided separately;

FIGS. 6 a-c: show a wiper drive with two stops provided separately; and

FIGS. 7 a-d show a wiper drive with a stop element which is slidablymounted in a swaying element.

In FIG. 1, a wiper drive as a whole bears the reference 2. The wiperdrive has a housing 4 for a reversing motor 6 and a gear mechanism 8connected downstream of the latter. The gear mechanism 8 is providedwith a gear mechanism output shaft 10 which projects out of the housing4 and at the end of which a swaying element 12 is placed, said swayingelement being non-releasably connected to the gear mechanism outputshaft 10. The non-releasable connection is configured as a pressconnection.

Provided at the end of the swaying element 12 remote from the gearmechanism output shaft 10 is a hinge pin 14 which is fixedly connectedto the swaying element 12 and serves to drive a wiper arm or a wiper armrod.

The housing 4 furthermore has a total of four threaded sockets 16 whichare arranged in pairs next to an elongate tube receiving area 18. Thetube receiving area 18 serves to receive a support frame designed as atubular element (cf. FIG. 1 b).

In FIG. 1 a, the wiper drive 2 is shown in its state at the start ofmounting. In FIG. 1 b, the tubular element 20 is additionally shown,said tubular element being placed in the tube receiving area 18delimited by the threaded sockets 16. The swaying element 12 is shown ina first swaying position 22 in FIG. 1 b.

In FIG. 1 c, the swaying element 12 is in a position pivoted through180° from the first swaying position 22 into the swaying position 24.Between the tubular element 20 which is also shown in FIG. 1 c and theswaying element 12 which is in the swaying position 24, an add-onelement 26 is pushed partially into the intermediate space formedbetween the tubular element 20 and the swaying element 12, in thepush-in direction 28. The add-on element 26 is designed as a shaped partmade of sheet metal and has a first stop holding section 30 for a firststop 32 which extends perpendicular to the plane of the drawing. Theadd-on element 26 furthermore has a second stop holding section 34 for asecond stop 36 which likewise extends perpendicular to the plane of thedrawing. The add-on element 26 is furthermore provided with a total offour through-holes 38, the arrangement of which corresponds to thearrangement of the threaded sockets 16 shown in FIG. 1 a. Thethrough-holes 38 in pairs delimit a tube retaining section 40 whichextends parallel to the tubular element 20.

In FIG. 1 d, the add-on element 26 is shown in the position which itassumes once mounting of the wiper drive 2 is complete. The add-onelement 26 is fixed in the threaded sockets 16 shown in FIG. 1 a byscrews 42 which pass through the through-holes 38 shown in FIG. 1 c. Thetubular element 20 is thus secured between the housing 4 and the tuberetaining section 40 of the add-on element 26.

The swaying element 12 as shown in FIG. 1 d has been pivoted by afurther 90° compared to the position 24 shown in FIG. 1 c, into a thirdswaying position 44. In the position shown in FIG. 1 d, the swayingelement 12 bears against the second stop 36. The stop 36 and the stop 32delimit a pivoting range 98, within which the swaying element 12 canmove. The operating range of the swaying element 12 lies within thepivoting range 98.

In FIG. 1 e, the securing of the tubular element 20 on the wiper drive 2is shown in detail. The tubular element 20 is received in a space whichis delimited towards the bottom by the housing 4 and to the sides by thethreaded sockets 16. The tubular element 20 is secured towards the topby the add-on element 26, which bears with its tube retaining section 40against the tubular element 20, by means of screws 42.

The mounting of the wiper drive 2 shown in FIGS. 1 a-1 e comprises atotal of five mounting steps. Firstly, the tubular element 20 is placedin the tube receiving area 18 of the housing 4 (cf. FIGS. 1 a and 1 b).In the second step, the swaying element 12 is pivoted from its firstposition 22 into its second position 24 (FIG. 1 c), and in a third stepthe add-on element 26 is pushed into the intermediate space between thetubular element 20 and the swaying element 12, in the push-in direction28 (FIG. 1 c). In a fourth mounting step, the add-on element 26 issecured on the housing 4, wherein the tubular element 20 is clampedsecurely (cf. FIGS. 1 d and 1 e). In a final mounting step, the swayingelement 12 is pivoted out of the position 24 shown in FIG. 1 c and intothe position 44 shown in FIG. 1 d.

The embodiments described below are based in principle on the originalmounting state of the wiper drive 2 as shown in FIG. 1 a. The referencesof FIG. 1 a have been retained for the embodiments shown in FIGS. 2 to7, with the references being increased in steps of 100 for eachembodiment. The wiper drive shown in FIG. 2 a thus bears the reference202. All components 204 to 218 which are shown in FIG. 2 a correspond tocomponents 4 to 18 shown in FIG. 1 a. Thus, in FIG. 2 a, a tubereceiving area 218 is provided which is delimited by pairs of threadedsockets 216. As shown in FIG. 2 b, a tubular element 220 is inserted inthe tube receiving area, said tubular element being fixedly connected toan add-on element 226. The add-on element 226 has a stop holding section230, at the end of which there is a first stop 232 which extendsperpendicular to the plane of the drawing. The add-on element 226 hastwo through-holes 238 which are provided on either side of a tuberetaining section 240 and are passed through by screws 242 which arefixed in the threaded sockets 216 shown in FIG. 2 a. The add-on element226 is connected to the tubular element 220 by a welded connection 246in the form of two spot welds.

In FIG. 2 c, the swaying element 212 has been pivoted by 270° in theclockwise direction compared to the swaying position 222 shown in FIG. 2b, into a second swaying position 224. In this position, the swayingelement 212 bears against the stop 232 of the add-on element 226.

There is furthermore a second add-on element 248 which has a stopholding section 250 on which a second stop 252 is arranged. The secondstop 252 likewise extends perpendicular to the plane of the drawing.

The second add-on element 248 has two through-holes 254 which arearranged on either side of a tube retaining section 256 and are passedthrough by screws 258 which are fixed in the threaded sockets 216 shownin FIG. 2 a. The stops 232 and 252 delimit a pivoting range 298 whichextends essentially over 180°.

The following mounting steps are required in order to mount the wiperdrive 202 shown in FIGS. 2 a-c. Firstly, the add-on element 226 is fixedon the tubular element 220 by means of the welded connection 246. Thetubular element 220 and the add-on element 226 are then supplied as anassembly to the housing 204 of the wiper drive 202, so that the tubularelement 220 is received in the tube receiving area 218. In the nextstep, the add-on element 226 is fixed to the housing 204 of the wiperdrive 202 by means of screws 242 (cf. FIG. 2 b). In the next step, theswaying element 212 is pivoted by 270°, out of the position 222 shown inFIG. 2 b and into the position 224 shown in FIG. 2 c, in which theswaying element 212 comes to bear against the stop 232 of the add-onelement 226. In the next step, the add-on element 248 is fixed to thehousing 204 of the wiper drive 202 by means of the screws 258.

The wiper drive 302 shown in FIG. 3 a corresponds essentially to thewiper drive 2 shown in FIG. 1 a. Additionally, a total of three fixingpoints 360, 362 and 364 are provided on the housing 304. The fixingpoints 360 to 364 are arranged on a circular path with respect to thegear mechanism output shaft 310 and at a distance of in each case 120°.

FIG. 3 b shows the wiper drive 302, in the tube receiving area 318 ofwhich a tubular element 320 is placed. Two retaining elements 366 arearranged on the tubular element 320, said retaining elements each havinga tube retaining section 368 in the centre. The retaining elements 366are non-releasably connected to the tubular element 320 via spot welds370. The retaining elements 366 have through-holes 372 on either side ofthe tube retaining sections 368, said through-holes being passed throughby screws 374 which are fixed in the threaded sockets 316 shown in FIG.3 a.

In FIG. 3 c, the swaying element 312 is shown pivoted by 270° withrespect to the position 322 shown in FIG. 3 b, into the position 324. Asshown in FIG. 3 c, an add-on element 376 is provided which is designedessentially as an arc of a circle and extends over approximately 240°.The add-on element 376 bears a first stop 378 at one of its free ends,and a second stop 380 at an angular spacing of approximately 120° fromthe first stop 378. The add-on element 376 is secured by means of threefixing elements 382, 384 and 386 at the fixing points 360, 362 and 364shown in FIG. 3 a. The stops 378 and 380 delimit a pivoting range 398which extends over approximately 180°.

The following steps are required in order to mount the wiper drive 302shown in FIGS. 3 a-c. Firstly, the retaining elements 366 are fixed tothe tubular element 320 via the welded connection 370. In the followingstep, the assembly consisting of tubular element 320 and retainingelements 366 is supplied to the wiper drive 302 and secured there bymeans of screws 374. In the next step, the swaying element 312 ispivoted by approximately 270°, out of the first swaying position 322 andinto the second swaying position 324. In the final mounting step, theadd-on element 376 is fixed by means of the fixing elements 382 to 386at the fixing points 360 to 364.

FIGS. 4 a-c show three modifications compared to the embodiment shown inFIGS. 3 a-c. The add-on element 476 used in the variant of FIG. 4 a doesnot extend over an angle of approximately 240° like the add-on element376 used in FIG. 3 c, but rather only over an angle of approximately120°. The add-on element 476 shown in FIG. 4 a has a stop 478 and 480 ateach of its ends. The add-on element 476 is fixed to the housing 404 ofthe wiper drive 402 a by means of two fixing elements 482 and 484. Thefixing point 464 of the wiper drive 402 a is not used in the variantshown in FIG. 4 a. The stops 478 and 480 delimit a pivoting range 498 aof the swaying element 412, said pivoting range extending overapproximately 240°.

In the variant shown in FIG. 4 b, the same add-on element 476 is used asin the wiper drive 402 a of FIG. 4 a. The add-on element 476 used inFIG. 4 b is fixed at the fixing points 462 and 464 (which are hidden inthe figure) by means of two fixing elements 484 and 486. The stops 478and 480 formed at the ends of the add-on element 476 delimit a pivotingrange 498 b which extends essentially over 240° and is offset byapproximately 120° in the clockwise direction compared to the pivotingrange 498 a shown in FIG. 4 a.

The add-on element 476 shown in FIG. 4 c is fixed by fixing elements 482and 486 at the fixing points 460 and 464. The add-on element 476delimits with its stops 478 and 480 a pivoting range 498 c which extendsessentially over 240° and is offset by approximately 120° in theclockwise direction compared to the pivoting range 498 b shown in FIG. 4b.

The embodiment of a wiper drive 502 shown in FIG. 5 a corresponds to thewiper drive 2 shown in FIG. 1 a. As shown in FIG. 5 b, placed in thetube receiving area 518 of the wiper drive 502 is a tubular element 520which is provided with a retaining element 566 which has a centrallyarranged tube retaining section 568 which is connected to the tubularelement 520 via spot welds 570. The retaining element 566 hasthrough-holes 572 which are passed through by screws 574 which are fixedin the threaded sockets 516 shown in FIG. 5 a. The housing 504 of thewiper drive 502 has a stop 588 which is formed in one piece with thehousing 504 and in which a step 590 is provided, said step facing thetubular element 520.

The housing 504 furthermore has a pin holder 592. As shown in FIGS. 5 cand 5 d, a pin 594 is inserted in the latter, said pin serving as asecond stop. The pin 594 extends essentially perpendicular to the planeof pivoting of the swaying element 512.

The following steps are required in order to mount the embodiment of thewiper drive 502 shown in FIGS. 5 a-d. Firstly, the retaining element 566is connected to the tubular element 520 via a spot weld. The tubularelement 520 together with the retaining element 566 is then supplied tothe wiper drive 502 and the tubular element 520 is inserted in the tubereceiving area 518 in the housing 504 of the wiper drive 502. In thenext step, the retaining element 566 is fixed to the housing 504 bymeans of screws 574. The swaying element 512 is then pivoted byapproximately 270°, out of a first swaying position 522 and into asecond swaying position 524 (cf. FIGS. 5 b and 5 c). The pin 594 is thenplaced in the pin holder 592 so that a pivoting range 598 of the swayingelement 512 is delimited by the stepped stop 588 and the pin 594.

The embodiment of a wiper drive 602 shown in FIGS. 6 a-c correspondslargely to the embodiment shown in FIGS. 5 a-d. Instead of a stopconnected in one piece with the housing, however, as shown in FIG. 6 b atotal of two stop holders 688 and 692 are provided, in which two pins690 and 694 are placed, as shown in FIG. 6 c, said pins in each caseserving as stops. The pins 690 and 694 are received in the respectiveholders 688 and 692, as has already been described with reference toFIG. 5 d.

The following steps are required in order to mount the embodiment of thewiper drive 602 shown in FIGS. 6 a-c. Firstly, the tubular element 620is connected to the retaining element 666 via a spot weld. The twocomponents are then supplied as an assembly to the wiper drive 602, andthe tubular element 620 is inserted in the tube receiving area 618. Theretaining element 666 is then fixed to the housing 604 by means ofscrews. In the next step, the swaying element 612 is pivoted byapproximately 270°, out of the swaying position 622 shown in FIG. 6 band into the swaying position 624 shown in FIG. 6 c. Finally, the pins690 and 694 are inserted in the holders 688 and 692. A pivoting range698 is now delimited by the pins 690 and 694, said pivoting rangeextending over approximately 180°.

FIGS. 7 a-d show another embodiment of the invention. The wiper driveshown in FIG. 7 a corresponds to the wiper drive 2 shown in FIG. 1 a. InFIG. 7 b, a tubular element 720 is connected to a retaining element 766via a spot weld, said retaining element in turn being connected to thehousing 704 of the wiper drive 702 by means of screws 774. The housing704 has two stops 788 and 792, which each have a step 790 and 794.

A stop element designed as a pin 796 is provided in the swaying element712, said stop element being displaceably mounted in the swaying element712. This is shown in detail in FIG. 7 d. In FIG. 7 d, the housing 704of the wiper drive 702 can be seen, which housing comprises the threadedsocket 716. Arranged next to the threaded socket 716 shown in FIG. 7 dis the tubular element 720 which is fixed to the housing 704 via theretaining element 766 and screws 774. The swaying element 712 shown atthe top in FIG. 7 d has a hinge pin 714 at its end, which hinge pinserves to drive a wiper arm or wiper arm rod (not shown). At the end ofthe swaying element 712 opposite the hinge pin 714, said swaying elementis connected to the gear mechanism output shaft 710 via a pressconnection.

Between the gear mechanism output shaft 710 and the hinge pin 714, theswaying element bears the pin 796 which is displaceably mounted in theswaying element 712. In the position shown in FIG. 7 d, the pin 796cooperates with the step 790 of the stop 788 so that the pivoting rangeof the swaying element 712 is delimited by the stop 788 and by the stop792. Overall, the swaying element 712 can assume positions which liewithin the pivoting range 798 (cf. FIG. 7 c).

The following steps are required in order to mount the wiper drive 702shown in FIGS. 7 a-d. Firstly, the retaining element 766 is connected tothe tubular element 720 via a spot weld. The assembly thus formed isthen supplied to the wiper drive 702 and fixed there to the housing 704via screws 774. In the next step, the swaying element 712 is brought outof the swaying position 722 shown in FIG. 7 b and into the swayingposition 724 shown in FIG. 7 c. The stop element 796 designed as a pinis then displaced in the direction of the housing 704, so that the pin796 can cooperate with the steps 790 and 794 of the stops 788 and 792.

All the embodiments described have the common feature that the wiperdrive can be mounted with few steps and very simple and cost-effectivemounting elements can be used.

1. Wiper drive comprising a housing, a reversing motor and a gearmechanism connected downstream of the reversing motor, wherein a swayingelement for driving at least one wiper arm or a wiper arm rod isprovided on the gear mechanism output shaft, and wherein the operatingrange of the swaying element lies within a pivoting range which isdelimited by two mechanical stops, characterized in that at least onestop is designed such that it can be removed and/or moved in such a waythat the swaying element, when the wiper drive is mounted on a supportframe, can be moved from a first mounting position, which lies outsidethe pivoting range, into the pivoting range without being obstructed bythe stop.
 2. Wiper drive according to claim 1, characterized in that atleast one stop is arranged on at least one add-on element such that itcannot be removed, wherein the add-on element can be releasably fixed ona component of the wiper drive, in particular on the housing.
 3. Wiperdrive according to claim 2, characterized in that two add-on elementsare provided, on each of which a stop is provided.
 4. Wiper driveaccording to claim 2, characterized in that at least one add-on elementis suitable for exerting a retaining function for a connection betweenthe housing and a support frame.
 5. Wiper drive according to claim 2,characterized in that the add-on element can be releasably fixed on acomponent of the wiper drive, in particular on the housing, in variousorientations and/or at various positions.
 6. Wiper drive according toclaim 2, characterized in that the add-on element can be fixed on acomponent of the wiper drive, in particular on the housing, at leastone, preferably at several, fixing points.
 7. Wiper drive according toclaim 2, characterized in that the add-on element is designed as ashaped part made of sheet metal.
 8. Wiper drive according to claim 2,characterized in that the add-on element is non-releasably connected tothe support frame.
 9. Wiper drive according to claim 8, characterized inthat the non-releasable connection is produced by welding, soldering,adhesive bonding or riveting.
 10. Wiper drive according to claim 1,characterized in that at least one stop is provided as a separatecomponent which can be fixed on a component of the wiper drive, inparticular on the housing.
 11. Wiper drive according to claim 10,characterized in that two stops are provided.
 12. Wiper drive accordingto claim 10, characterized in that the at least one stop is provided asa pin.
 13. Wiper drive according to claim 12, characterized in that thepin is slidably arranged in a component of the wiper drive, inparticular in the housing, and extends essentially perpendicular to theplane in which the swaying element moves.
 14. Wiper drive comprising ahousing, a reversing motor and a gear mechanism connected downstream ofthe reversing motor, wherein a swaying element for driving at least onewiper arm or a wiper arm rod is provided on the gear mechanism outputshaft, and wherein the operating range of the swaying element lieswithin a pivoting range which is delimited by two mechanical stops,characterized in that the stops cooperate with a stop element which isprovided on or in the swaying element such that it can be moved and/orremoved.
 15. Wiper drive according to claim 14, characterized in thatthe stops are made in one piece with a component of the wiper drive, inparticular with the housing.
 16. Wiper drive according to claim 1,characterized in that the support frame is designed as a tubularelement.
 17. Wiper drive according to claim 1, characterized in that theswaying element is non-releasably connected to the gear mechanism outputshaft.
 18. Method for mounting a wiper drive on a support frame, whereinthe wiper drive comprises a housing, a reversing motor and a gearmechanism connected downstream of the reversing motor (206), wherein aswaying element for driving at least one wiper arm or a wiper arm rod isprovided on the gear mechanism output shaft, and wherein the operatingrange of the swaying element lies within a pivoting range which isdelimited by two mechanical stops, characterized by the following steps:a) mutual orientation and positioning of housing and support frame,wherein the swaying element assumes a position outside its pivotingrange, b) mounting of a first stop on a component of the wiper drive, inparticular on the housing, c) fixing of the housing on the supportframe, d) pivoting of the swaying element into the pivoting range, e)mounting of a second stop on a component of the wiper drive, inparticular on the housing.
 19. Method for mounting a wiper drive on asupport frame according to claim 18, wherein the steps are carried outin the order a), d), b), e), c).
 20. Method for mounting a wiper driveon a support frame according to claim 18, wherein the steps are carriedout in the order a), c), d), b), e).
 21. Method for mounting a wiperdrive on a support frame according to claim 20, wherein steps b) and e)are replaced by the displacement of a stop element which is provided onor in the swaying element such that it can be moved and/or removed. 22.Method according to claim 18 for mounting a wiper drive according toclaim 1.